/* Copyright (c) 2007 Scott Lembcke
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <stdlib.h>

#include "../chipmunk.h"
#include "util.h"

static void
preStep(cpBreakableJoint *breakable, cpFloat dt, cpFloat dt_inv)
{
	cpConstraint *delegate = breakable->delegate;

	if(delegate->klass->getImpulse(delegate)*breakable->last_dt_inv >= breakable->constraint.maxForce){
		cpSpaceRemoveConstraint(breakable->space, (cpConstraint *)breakable);
//		cpConstraintFree(constraint);
		
		return;
	}
	
	delegate->klass->preStep(delegate, dt, dt_inv);
	breakable->last_dt_inv = dt_inv;
}

static void
applyImpulse(cpBreakableJoint *breakable)
{
	cpConstraint *delegate = breakable->delegate;
	delegate->klass->applyImpulse(delegate);
}

static cpFloat
getImpulse(cpBreakableJoint *breakable)
{
	cpConstraint *delegate = breakable->delegate;
	return delegate->klass->getImpulse(delegate);
}

static const cpConstraintClass klass = {
	(cpConstraintPreStepFunction)preStep,
	(cpConstraintApplyImpulseFunction)applyImpulse,
	(cpConstraintGetImpulseFunction)getImpulse,
};
CP_DefineClassGetter(cpBreakableJoint)


cpBreakableJoint *
cpBreakableJointAlloc(void)
{
	return (cpBreakableJoint *)malloc(sizeof(cpBreakableJoint));
}

cpBreakableJoint *
cpBreakableJointInit(cpBreakableJoint *breakable, cpConstraint *delegate, struct cpSpace *space)
{
	cpConstraintInit((cpConstraint *)breakable, &klass, NULL, NULL);
	
	breakable->delegate = delegate;
	breakable->space = space;
	
	return breakable;
}

cpConstraint *
cpBreakableJointNew(cpConstraint *delegate, struct cpSpace *space)
{
	return (cpConstraint *)cpBreakableJointInit(cpBreakableJointAlloc(), delegate, space);
}
